One-dimensional porous nanofibers of Co₃O₄ on the carbon matrix from human hair with superior lithium ion storage performance

One-dimensional (1D) hierarchical porous nanofibers of Co₃O₄ possessing of (220) facets on the carbon matrix from human hair (H2@Co₃O₄) with 20-30 nm in width and 3-5 μm in length are prepared by a facile solvothermal and calcination approach. The well crystallized small Co₃O₄ particles with the diameter of about 8-12 nm were closely aggregated together in the nanofibers. Electrochemical analyses show that the first discharge capacity of H2@Co₃O₄ electrode is 1368 mAh g^-1 at the current density of 0.1 A g^-1 based on the total mass of composite. A high reversible capacity of 916 mAh g^-1 was obtained over 100 cycles at 0.1 A g^-1, presenting a good cycling stability. When cycled at a high current density of 1 and 2 A g^-1, the specific capacity of 659 and 573 mAh g^-1 could be still achieved, respectively, indicating a superior power capability.